In Jupyter Lab I have seattle-weather.csv, bar.vl.json and a notebook all in the same folder. The data is from the example data sets, as is the Vega Lite:

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "data": {"url": "seattle-weather.csv"},
  "mark": "bar",
  "encoding": {
    "x": {"timeUnit": "month", "field": "date", "type": "ordinal"},
    "y": {"aggregate": "count", "type": "quantitative"},
    "color": {"field": "weather", "type": "nominal"}
  }
}

Opening the Vega Lite file directly creates a tab with the bar chart rendered as expected. In the notebook I need to pass the full URL to Altair to create the same visualisation:

alt.Chart('http://localhost:8888/files/seattle-weather.csv').mark_bar().encode(
    x='month(date):O',
    y='count():Q',
    color='weather:N'
)

Why does alt.Chart('seattle-weather.csv')..... not work in the notebook? Can the docs be updated to include guidance around this use case scenario?